1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2011, 2019 by Delphix. All rights reserved. 24 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 25 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. 26 * Copyright 2013 Saso Kiselkov. All rights reserved. 27 * Copyright (c) 2014 Integros [integros.com] 28 * Copyright 2017 Joyent, Inc. 29 * Copyright (c) 2017 Datto Inc. 30 */ 31 32 #ifndef _SYS_BITOPS_H 33 #define _SYS_BITOPS_H 34 35 #include <sys/zfs_context.h> 36 37 #ifdef __cplusplus 38 extern "C" { 39 #endif 40 41 /* 42 * General-purpose 32-bit and 64-bit bitfield encodings. 43 */ 44 #define BF32_DECODE(x, low, len) P2PHASE((x) >> (low), 1U << (len)) 45 #define BF64_DECODE(x, low, len) P2PHASE((x) >> (low), 1ULL << (len)) 46 #define BF32_ENCODE(x, low, len) (P2PHASE((x), 1U << (len)) << (low)) 47 #define BF64_ENCODE(x, low, len) (P2PHASE((x), 1ULL << (len)) << (low)) 48 49 #define BF32_GET(x, low, len) BF32_DECODE(x, low, len) 50 #define BF64_GET(x, low, len) BF64_DECODE(x, low, len) 51 52 #define BF32_SET(x, low, len, val) do { \ 53 ASSERT3U(val, <, 1U << (len)); \ 54 ASSERT3U(low + len, <=, 32); \ 55 (x) ^= BF32_ENCODE((x >> low) ^ (val), low, len); \ 56 _NOTE(CONSTCOND) } while (0) 57 58 #define BF64_SET(x, low, len, val) do { \ 59 ASSERT3U(val, <, 1ULL << (len)); \ 60 ASSERT3U(low + len, <=, 64); \ 61 ((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len)); \ 62 _NOTE(CONSTCOND) } while (0) 63 64 #define BF32_GET_SB(x, low, len, shift, bias) \ 65 ((BF32_GET(x, low, len) + (bias)) << (shift)) 66 #define BF64_GET_SB(x, low, len, shift, bias) \ 67 ((BF64_GET(x, low, len) + (bias)) << (shift)) 68 69 /* 70 * We use ASSERT3U instead of ASSERT in these macros to prevent a lint error in 71 * the case where val is a constant. We can't fix ASSERT because it's used as 72 * an expression in several places in the kernel; as a result, changing it to 73 * the do{} while() syntax to allow us to _NOTE the CONSTCOND is not an option. 74 */ 75 #define BF32_SET_SB(x, low, len, shift, bias, val) do { \ 76 ASSERT3U(IS_P2ALIGNED(val, 1U << shift), !=, B_FALSE); \ 77 ASSERT3S((val) >> (shift), >=, bias); \ 78 BF32_SET(x, low, len, ((val) >> (shift)) - (bias)); \ 79 _NOTE(CONSTCOND) } while (0) 80 #define BF64_SET_SB(x, low, len, shift, bias, val) do { \ 81 ASSERT3U(IS_P2ALIGNED(val, 1ULL << shift), !=, B_FALSE); \ 82 ASSERT3S((val) >> (shift), >=, bias); \ 83 BF64_SET(x, low, len, ((val) >> (shift)) - (bias)); \ 84 _NOTE(CONSTCOND) } while (0) 85 86 #ifdef __cplusplus 87 } 88 #endif 89 90 #endif /* _SYS_BITOPS_H */ 91